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op-amp current sensing problem

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mshh

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i tested the attached circuit again but i forgot to connect pin3 ( red circle ) the chip got hot and burnt up for the second time . i don't know why . also i measured the signal on zero ohm resistor it was 8.3 mv the output was .83 volt which mean that the gain is 101 not 51 however gain=1+1000/20 = 51 , i also tried another resistor and i got the same results the output multiplied by 2 ,i tried lm358 and it give the same results.
 

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mshh

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With R4 being .006 ohms every bit of wire in the current monitoring circuit will drop some voltage, is R7 returned to exactly the end of R4?
Frank
yes , i made all the resistors closed as possible as i can .gain isn't correct
 

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